I have a subroutine that measures tool lengths, used mainly because the tool.tbl has no entries suitable for measuring or characterizing taps, but since the shank drill also changes depending on the tap hat being made, I've used this in a subroutine to give me an offset to be used in the next operation.
It looks like this: g38.2 f160 z-80 (go fast, don't need ultra precision here ) G92 Z25.0000000 ( adjust this to make all #<_vars> positive ) ( get tool off contact pad ) But if something goes wrong, and I restart from the top with this offset in effect it can move in the wrong direction and break things. I have, at various points after an operation based on this offset, put in a canceling command that is outside of this subroutine, but with no exceptions, all vars are global, so the subroutine should not effect the scope of these changes in the z reference. But it seems I am not getting, with a g92.1 or a g92.2, the effect I want. And the error can be 100mm or more, breaking drill bits etc. So what is the approved, cancels it all g92.x command, Yesterday its first move was supposed to be to z150, room to change tools. It was sitting at about 0z, having just drilled the shank hole in a new brass cylinder, and I had lifted it by hand jog enough to pull the drilled brass slug and had placed it in the rotary tables R8 where the 4 holes at 90 degree intervals would be bored next. When I hit r, it should have risen to z150, moved toward the center of the table, then to a contact pad location to then descend and measure the drill 1/8" for a 4x.7 tap ending at the above code. But instead of rising, it went down at 1700mm/min, pushing the 1/8" bit right down the axis of the .199 shank bit still sticking up out of the chuck fixed to the table, and of course breaking that bit when the spindle came up to drilling speed at the end of that move. So that first move to z150, intended to get clearance from the forest of jigs etc sticking up from the table, was totally wrong. So, can the g92.1 or G92.2 be over-used, potentially creating this scenario? The docs don't explicitly say. I'll go back and ascertain that I am not putzing with the #5211-#5219 stuff as that reads like disaster making. So a g92.2 should be the correct cancel the offset command in my mind. And I just found a g92.1. Boom. Bet thats it. Stay tuned. -- Cheers, Gene Heskett -- "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author) Genes Web page <http://geneslinuxbox.net:6309/gene> ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, Slashdot.org! http://sdm.link/slashdot _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
